Spotter scope for 12' Dob

hey all,

Is there any reason why a 70mm f500 would make a significantly worse
finder scope than a 80mm f400? other than the apperture issue? I was
going to get a ST80 but I've the chance to buy a 70mm quite a bit
cheaper and it comes with a red dot finder (unlike the ST80)?
any thoughts?

Gaz

hey all,

Is there any reason why a 70mm f500 would make a significantly worse
finder scope than a 80mm f400?

I would be concerned about the weight because of possible balance issues as
well whether it can use 2 inch eyepieces.

If you are limited to 1.25 inch eyepieces, an 80mm F5 scope with a 32 mm Plossl
can have a 4 deg FOV where as the longer focal length scope will be limited to
3.2 degrees.

Personally I think a good 50mm with a 7 degree FOV is nice... Lets me find the
stuff without getting overwhelmed when the skies are dark...

jon

hey all,

Is there any reason why a 70mm f500 would make a significantly worse
finder scope than a 80mm f400?

I would be concerned about the weight because of possible balance issues as
well whether it can use 2 inch eyepieces.

If you are limited to 1.25 inch eyepieces, an 80mm F5 scope with a 32 mm Plossl
can have a 4 deg FOV where as the longer focal length scope will be limited to
3.2 degrees.

Personally I think a good 50mm with a 7 degree FOV is nice... Lets me find the
stuff without getting overwhelmed when the skies are dark...

jon

Gaz

I agree with Jon on this one. A 50mm would be a good bet for the 12".
A 70mm would work but you would have to find one that balanced well.

I have the ST80 on my 16 which balances very well but it may not for
you. see attached photo. It dosent have the star diagonal thats usally
on it but the picture shows you how it would look.

Regards

Rich


On 12 Feb 2004 00:50:36 GMT, (Jon Isaacs) wrote:

hey all,

Is there any reason why a 70mm f500 would make a significantly worse
finder scope than a 80mm f400?

I would be concerned about the weight because of possible balance issues as
well whether it can use 2 inch eyepieces.

If you are limited to 1.25 inch eyepieces, an 80mm F5 scope with a 32 mm Plossl
can have a 4 deg FOV where as the longer focal length scope will be limited to
3.2 degrees.

Personally I think a good 50mm with a 7 degree FOV is nice... Lets me find the
stuff without getting overwhelmed when the skies are dark...

jon

Gaz

I agree with Jon on this one. A 50mm would be a good bet for the 12".
A 70mm would work but you would have to find one that balanced well.

I have the ST80 on my 16 which balances very well but it may not for
you. see attached photo. It dosent have the star diagonal thats usally
on it but the picture shows you how it would look.

Regards

Rich


On 12 Feb 2004 00:50:36 GMT, (Jon Isaacs) wrote:

hey all,

Is there any reason why a 70mm f500 would make a significantly worse
finder scope than a 80mm f400?

I would be concerned about the weight because of possible balance issues as
well whether it can use 2 inch eyepieces.

If you are limited to 1.25 inch eyepieces, an 80mm F5 scope with a 32 mm Plossl
can have a 4 deg FOV where as the longer focal length scope will be limited to
3.2 degrees.

Personally I think a good 50mm with a 7 degree FOV is nice... Lets me find the
stuff without getting overwhelmed when the skies are dark...

jon